1. Field of the Invention
This invention relates to tamper-proof valves and more particularly, to a locking assembly for rendering valves tamper-proof, which valves include a valve body fitted with an inner body, a top valve assembly closure and the locking assembly components. In a preferred embodiment these components include a spring-loaded key slidably located in a square opening provided in a collet disposed between the top valve assembly and the inner body. An allen screw having a tamper-proof tool receptacle is threaded in the top valve assembly and serves to engage and disengage the locking assembly by seating against the top of the key and forcing the key downwardly against the bias of a coil spring, also located in the collet opening. This action removes the top portion of the key from a key seat located in the top valve assembly and facilitates rotation of the top valve assembly independently of the inner body. Operation of the valve is effected by rotating the allen screw in the opposite direction to reduce tension on the spring, allow the key to move upwardly and seat in the key seat and facilitate manipulation of the top valve assembly and inner body in concert into the open or closed position. The allen screw is characterized by a tamper-proof design, wherein a tamper-proof pin is located in the wrench receptacle to accommodate a corresponding allen wrench having a pin opening for matching the pin. The tamper-proof valve of this invention can be used to control the flow of gases and liquids, as well as slurries and the like, in a wide variety of applications involving substantially any fluid. The tamper-proof valve is primarily designed for use on conventional consumer gas meters to quickly and easily prevent unauthorized use of the gas meters.
One of the problems which exists in conventional gas meters is that of preventing the flow of gas through the meters under circumstances where gas consumer service is terminated due to nonpayment of user's bills or for other reasons. Probably the most commonly used technique for terminating gas service is locking the service line valve into the closed position with a padlock. However, the lock can be easily removed with a bolt cutter and the gas service illegally restored. Accordingly, the only sure way of interrupting gas service to a user is to remove the gas meter, which requires initially terminating the gas flow at the service line valve and then removing the gas meter valve by a service man.
2. Description of the Prior Art
Various valves having locking mechanisms are known in the art and typical of these designs are the valves detailed in the following U.S. Pat. Nos.: 1,855,414; 2,161,509; 2,309,304; 2,399,578; 2,748,974; 4,465,092; and 4,534,379.
It is an object of this invention to provide a tamper-proof gas meter valve which is mounted in the gas service line with a conventional gas meter and can be quickly and easily operated with a specially equipped allen wrench to terminate the gas service and subsequently restore gas service, as necessary.
A still further object of this invention is to provide an all-purpose tamper-proof valve which is designed to be opened and closed by manipulation of a tamper-proof tool such as a specially-equipped allen wrench, to selectively seat and unseat a spring-loaded key located in the interior of the valve by threadable manipulation of the allen screw.
Still another object of the invention is to provide a tamper-proof valve which is characterized by a conventional valve body and a specially designed inner body and top valve assembly which accommodate a key slidably mounted in a collet against the bias of a spring located between the inner body and the top valve assembly, wherein the key is selectively manipulated into and from a key seat located in the top valve assembly by operation of an allen screw having a tamper-proof tool receptacle and threadably seated in the top valve assembly.
Yet another object of this invention is to provide a tamper-proof locking assembly for installation in a valve and rendering the valve tamper-proof, which locking assembly includes a key seat shaped in the top valve assembly of the valve, a key adapted for slidably engaging and disengaging the key seat, and a collet having a collet opening for receiving a coil spring seated on the inner body of the valve and contacting one end of the key, wherein the key engages the spring such that threadable advancement of an allen screw located in the top valve assembly unseats the key from the key slot and allows rotation of the top valve assembly independently of the inner body, and threadable advancement of the allen screw in the opposite direction allows the spring to reseat the key in the key slot and facilitate rotation of the top valve assembly and the inner body in concert.